Pretreatment of Automotive Shredder Residues, Their Chemical Characterisation, and Pyrolysis Kinetics

Automotive Shredder Residue (ASR), a waste when metals are mostly removed from end-of-life vehicles, has constituents similar to municipal solid waste (MSW) consisting of plastics, rubber, textiles, and some metals. The processing of ASR is a challenge due to its heterogeneous nature, making feeding to a reactor difficult. In this work, a new procedure of ASR pretreatment is proposed to bring particulate nature in the sample for easier feeding during pyrolysis. The thermal breakdown characteristics of the pretreated ASR solids under slow pyrolysis conditions were assessed in a thermogravimetric analyser following the International Confederation for Thermal Analysis and Calorimetry (ICTAC) kinetics committee recommendations. The effect of particle sizes and heating rates were studied at temperatures up to 800 °C at different heating rates of 2, 5, and 10 °C/min for three particle sizes, 38–63 µm, 63–90 µm, and 90–106 µm, and the kinetic data were derived. The volatiles emitted during pyrolysis were characterized by Diffuse Reflectance Infrared Spectroscopy (DRIFTS). We also developed an algorithm for the selection of heating rate during the pyrolysis of the pretreated ASR. The DRIFTS results, kinetic data, and heating rate for the selected particle sizes are useful for the development of a pyrolysis process for pretreated ASR.

Infrared Characterization and Electrochemical Study of Silanes Grafted into Surface of Copper

The formation of a protective layer of tow silane coupling agents: γ -methacryloxypropyltrimethoxysilane (γ-MPS) or γ-aminopropyltriethoxysilane (γ-APS) on copper is studied by diffuse reflectance infrared spectroscopy (DRIFT), electrochemical (Potentiodynamic polarization) and gravimetric chemical (Weight loss) measurements. Dried in ambient conditions, the silane adsorbed on the copper subtract physically, however its protective action is not reliable. Thiolate and siloxane band formation ameliorate the protective action of the silanic layer on the surface of copper especially after curing process. Potentiodynamic polarization and Weight loss experiments show that the performances protective action of cured treatment (cured/Cu-silane) is higher than that of aging process (aged/Cu-silane).

1,3-Dimethyl-tetrakis(2-triphenylsilylethyl)dimethyldisiloxane: a new carbosilane for the preparation of high-refractive-index films

A new carbosilane has been synthesised in one step by hydrosilylation of 1,3-dimethyl-tetravinyldisiloxane with triphenyl silane. The new carbosilane has been characterized by 1D and 2D NMR, MS, and Gel Permeation Chromatography (GPC). The new carbosilane has been spin-coated on silicon wafers to prepare a film with very high refractive index (μ = 1.520) and excellent hydrophobicity. The film has also been analysed by Diffuse Reflectance Infrared Spectroscopy (DRIFT). The preparation of the new carbosilane does not generate waste, and its application can be easily scaled-up. Consequently, the new precursor is likely to be very useful for industrial optoelectronic applications.

Síntesis y caracterización de biovidrios de fosfato por el método pirólisis de aerosol en llama

Empleando el novedoso método pirólisis de aerosol en llama (FSP) se sintetizó por primera vez un biovidrio de fosfato de calcio en el sistema P2O5-CaO-Na2O. Las muestras obtenidas se caracterizaron mediante difracción de rayos X (DRX) y espectroscopía infrarroja de reflectancia difusa (DRIFTS), sirviendo esta última para seguir la cinética de biomineralización in-vitro durante 15 días en fluido corporal simulado (SBF). Mediante DRX se validó la naturaleza amorfa del biovidrio exhibiendo la fase whitlockita. El análisis DRIFTS reveló las bandas características de los grupos fosfatos en un rango de alrededor de los 500 a 1400 cm-1. Respectivamente, la evolución de las bandas de fosfatos en las muestras sumergidas en SBF indican la formación de apatita, proceso que siguió una cinética de pseudo- primer-orden de Lagergren. Using the novel flame aerosol pyrolysis method (FSP), a calcium phosphate bioglass was synthesized for the first time in the P2O5-CaO-Na2O. The samples obtained were characterized by X-ray diffraction(XRD) and diffuse reflectance infrared spectroscopy (DRIFTS), the latter serving to follow in-vitro biomineralization kinetics for 15 days in simulated body fluid (SBF). Using XRD, the amorphous nature of the bioglass was validated by exhibiting the whitlockite phase.The DRIFTS analysis revealed the characteristic bands of the phosphate groups in a range of about 500 to 1400 cm-1. Respectively, the evolution of the phosphate bands in the samples submerged in SBF indicate the formation of apatite, a process that followed a pseudo-first-order Lagergren kinetics.

Trends in the thermal stability of two-dimensional covalent organic frameworks

Here, we study the thermal stability of ten 2D covalent organic frameworks using a combination of variable-temperature X-ray diffraction, thermogravimetric analysis, diffuse reflectance infrared spectroscopy, and density-functional theory.

Polylactide Used as Filment in 3D Printing – Part 1: FTIR, DRIFT and TG-DTG Studies

A short literature review was undertaken in terms of the structure, properties and applications of polymers, including those commonly used in 3D printing. The research part included the structural and thermal analysis of polylactide (PLA), which is an example of an extensively used polymer in the developing 3D technology. Special attention was paid to the comparison of structure and thermal stability of two different (from various producers) polylactide samples. The research, involving such analytical methods as infrared spectroscopy (FTIR) and diffuse reflectance infrared spectroscopy (DRIFT), allowed the comparison of the structure of the two PLA samples considered. The determination of the temperature range in which changes related to PLA thermodestruction occur was a result of the performed thermoanalytical research (DRIFT, TG-DTG). Thermal studies also allowed to establish the temperature range in which the material does not yet degrade, which is important in the context of future planned research work on polylactide modification to obtain the improvement of the thermal and mechanical properties of PLA-based materials. This research area will be described in the second part of the publication.